What battery for Winnie Drop TT

Greg Morrow · 08-27-2021, 08:39 AM

It'a been 4 years, time to replace the battery on my winnie drop. Does a maitenance free betttery last longer, cost more? are there any advantages to them other than the obvious? I tried to search this, but search tunction takes out of the forum.

**ThomB** · 08-27-2021, 08:47 AM

I'd probably look at an AGM. Not sure they last longer, but they are sealed and pretty simple to maintain. I hated having to dig into the rv to check the fluid levels in the lead acid batteries. I currently have sealed lead acid batteries, but only because we're selling. They're all new, but not AGM.

Greg Morrow · 08-27-2021, 09:41 AM

Not sure what AGM is?? I'm not the guy who going to do regular battery maint. Take the propane cover off, fight with bat case strap, the case top is wedged in place, and I can't really see into the cells that well once i get that far. I would assume that the elec sys/converter in the trailer is set up to not destroy my battery. In the winter I take it off check the fluid level and put it on tender that is supposed to keep it topped off with out cooking it. Is 4 years of life typical? I read that lithium can't be used without replacing or modifing the converter. Also is cost prohibitive. Also what's the best place to but one, RV center, costco, walmart, autozone, etc.

**creativepart** · 08-27-2021, 09:57 AM

Quote:

Originally Posted by Greg Morrow

Not sure what AGM is??

AGM = Absorbed Glass Mat. Because of the construction you never add water to the battery.

Quote:

Originally Posted by Greg Morrow

I would assume that the elec sys/converter in the trailer is set up to not destroy my battery.

Well, no. It's up to you to insure that your battery is well cared for. The converter in your Drop is most likely a "dumb" charger and not very capable.

Quote:

Originally Posted by Greg Morrow

In the winter I take it off check the fluid level and put it on tender that is supposed to keep it topped off with out cooking it.

All that is great. Good job. Many do this anytime the TT will be stored for any period of time.

Quote:

Originally Posted by Greg Morrow

Is 4 years of life typical?

Actually, that's not too bad for a FLA battery (Flooded Lead Acid) in a travel trailer.

Quote:

Originally Posted by Greg Morrow

I read that lithium can't be used without replacing or modifing the converter. Also is cost prohibitive.

That is all true. $500 to $1000 for one 100 aH LiPo battery and it's pretty much a given that the Drop doesn't have a Lithium capable charger.

Quote:

Originally Posted by Greg Morrow

Also what's the best place to but one, RV center, costco, walmart, autozone, etc.

RV Center will probably be too expensive. The others will not have a true deep cycle battery. They pretty much only carry Marine/RV Dual Purpose batteries. They are not true deep cycles and in general I doubt you'll get 4-years out of one.

Amazon is a good place. You need to know the size of battery your battery box can hold. Usually, this is by "Group" number. The Drop could have come with a Group 24, 27 or 31 battery.

Each size larger is a more capable battery by amp hours available.

Look for a Battery that features it's Amp Hours not it's CCA or Cold Cranking Amps. When you see the CCA featured that's an engine starting battery and not a true deep cycle.

If your battery box is large enough for a Group 31 you will get 100 aH which should give you plenty of power for the Drop.

**ThomB** · 08-27-2021, 12:27 PM

Quote:

Originally Posted by Greg Morrow

Also what's the best place to but one, RV center, costco, walmart, autozone, etc.

Creativepart pretty much answered much better than I could have. I'll just address the part about where to go. We found a local to us (St. Pete, FL) mom-n-pop battery store. They had AGM's about $50 cheaper than anyone else locally could touch. You're not getting a known name brand though. I'm saying this as you can check if you have any shops local to you. It's worth an hour of time to shop around.

Greg Morrow · 08-27-2021, 01:05 PM

Thanks a bunch, this all helps. I have a 100w solar with controller, and a Champion 2500w gen. I only need the bat to last 24hrs using water pump, and whatever elec fridge uses on gas, and limited led lighting. This of course assumes the battery will recharge in the 2 hrs the NP lets you run the gen every morning. You can tell I'm inexperienced with this. Last year I only had the solar, which was useless in Shenandoah, but worked pretty well in Assateague. I haven't even unboxed the gen yet.

Marine359 · 09-01-2021, 08:42 AM

Quote:

Originally Posted by Greg Morrow

Thanks a bunch, this all helps. I have a 100w solar with controller, and a Champion 2500w gen. I only need the bat to last 24hrs using water pump, and whatever elec fridge uses on gas, and limited led lighting. This of course assumes the battery will recharge in the 2 hrs the NP lets you run the gen every morning. You can tell I'm inexperienced with this. Last year I only had the solar, which was useless in Shenandoah, but worked pretty well in Assateague. I haven't even unboxed the gen yet.

The amount of time needed to recharge is dependent on how big your battery is, and how much charge current it can accept. Also note that if you have the Champion DF, it will produce much lower watts on propane, but likely enough to max out your battery charger as long as you don’t try to use an inverter for other loads at the same time. A FLA or AGM battery goes through 3 charge phases, so charging from 30% to 100% can take 6 or 7 hours. LiFePo4 can be safely charged at 80amps. I charge mine from 30% to 100% in less than 2 hours, running my Champion on propane. This works out great because we just came from Acadia NP where allowed morning generator time was only 2 hours. Our solar was useless due to canopy and overcast skies. So for NP with short charge times, LiFePo4 is ideal, but it will require a large upfront investment; $500 or more for the battery, and $500 or more for a charger and transfer switch; or $700 for a 2000w inverter charger.

Morich · 09-01-2021, 09:12 AM

So much depends on the way we each use the RV and that involves looking at how much of each type of camping and what electrical we use. It sounds like you do not do a lot of electronics like TV, etc. but use the battery for the lights, etc, so that means you likely do not need the great deal of expense involved with lithium, etc but perhaps want to avoid the work involved in watching lead acid carefully to keep the water from boiling out.

All that sounds like it might make AGM a good mid range choice. It has good points on time to recharge and how low to discharge as well as NO work to keep the water in them. A touch higher but I feel worth paying for the ease and lasting value.

I look for amp hour rating and do not want CCA as that is the amount of quick power you need for starting engines which is NOT needed. Just lots of slower power for your smaller uses.
I shop online at all sources that show up, find what fits my space and look for the bigger amp hours at a price I want. There are tons of brands but only a few battery factories and lots of the rest is to pay for the adverts to sell the same battery!

DavidM · 09-01-2021, 10:27 AM

Before I got my MH, I had a simple TT like the Drop. We used it like you seem to do: no TV just lights, absorption fridge controls. water pump, device charging. It used 15 amp hours daily.

An AGM Group 27 (if that is all that will fit) will last three nights and a Group 31 should last five nights while boondocking with no solar.

With your 100 watts of solar, you should be able to go indefinitely no matter what type of battery you have, but I would still install a G27 or G31 AGM battery.

Amazon has 100 Ah Windynation AGMs for less than $200.

David

1Albert2 · 09-01-2021, 04:28 PM

You guys are great. I too have a Winnie Drop that's in it's third year. Will archive this article so when I need a new battery in the next year or so I can reference it. Right now the TT is in repair after being mugged by a dumpster. Thanks to all for the info.

BobC · 09-01-2021, 06:16 PM

Be aware that, although places like Sam's Club carry AGMs they characterize as "deep cycle", they're really dual purpose and not what you need (note CCA in its specs and "Marine & RV" in its name):

https://www.samsclub.com/p/duracell-...gm/prod3590232

You should ensure that your converter has a multi-stage "smart" charger. It will make your batteries last longer. This is what I purchased to upgrade mine:

https://www.amazon.com/Powermax-Supp...0541549&sr=8-2

They're available in different amp ratings. Try to match the rating of your existing converter since that's what the wiring is designed to handle.